This invention relates to shuttleless looms with weft-inserting needles and more especially to looms of the so-called "flying needle" type in which the inner extremity or head of each needle rests freely on the bottom layer of warp threads in proximity to the reed whilst the outer extremity of said needle is freely pivoted to a driving member to which is imparted a reciprocating movement in the axial direction of the needle. In looms of this type, all the needle guides located inside the shed are dispensed with, the needles being accurately maintained under the action of gravity and inertia within the dihedral angle made by the bottom layer of warp threads with the plane of the reed. Looms of this type have been described in French patent No. 1,290,867.
The invention applies to looms of the aforesaid type, whether they have either a single or a double layer of warp threads but is of particular interest in the case of double-layer looms.
Up to the present time, the needle (or the two twin needles in the case of a double-layer loom) was pivoted, for example by means of a universal joint, directly to the extremity of an oscillating lever which is mounted so that the extremity of this latter (which constitutes the actuating member aforesaid) carries out a rectilinear back-and-forth movement.
By reason of the fact that the oscillating lever aforesaid is of relatively substantial length (approximately 80 cm) and the fact that said lever is rotatably mounted and guided on members which are in turn capable of motion, said lever must be endowed with a high degree of rigidity in order to prevent vibrations of its upper extremity to which the needle is coupled.
It has become apparent, however, that when an attempt is made to increase the speed of the loom or when the lever is intended to actuate two needles (in the case of double-layer looms), this results in vibrations which have a harmful effect on the upper extremity of the lever and consequently on the needle or needles in spite of any steps which may be taken to increase the rigidity of the lever.